The two engineers looked at each other, locked in an unspoken duel over who should respond.

“An embellished CO2 report saves the plant both money and bad press,” Gitte finally replied.

“How does it save the plant money?” Larsen asked.

“When you burn trash, the CO2 emissions are measured, because they contribute to global warming. With the EU’s emissions trading system, CO2 quotas need to be bought, and they’re expensive. Just one year’s worth of quotas costs at least twenty million kroner. Are you following me so far?”

“I’m no idiot,” Larsen snapped, insulted.

Gitte did not seem convinced.

“The municipality of Copenhagen,” she continued, “wants to be CO2 neutral and demands that we comply with the agreed-upon level of emissions. At the same time, the plant is forced to import waste from the UK to incinerate more and supply more energy, which is how we earn money. So there are conflicting interests. But if you cheat by making the emissions numbers look lower, the plant saves money on CO2 quotas.”

“It can’t be that easy to cheat.” Jeppe shook his head. “There must be external controls, right?”

“Of course. An outside company collects data and calculates the values at a so-called QAL2-check, which is supposed to detect any major discrepancies. But that kind of check is only done once every three years.” Gitte’s cheeks had turned red. “The next QAL2 is scheduled for next week, actually. That’s why we were looking through the numbers.”

Jeppe felt suddenly disgusted by the whole situation. By the fraudulent order and the carbon calculations. By loving a woman who was shutting him out.

“Does Kasper keep a computer here?” he asked. “Can you open it?”

Neither of them answered.

“Let me remind you that we’re here in connection with a homicide investigation, and that obstructing or withholding relevant information is a criminal offense.” Jeppe looked from the one engineer to the other. “We need to find out what’s going on.”

Jim got up and walked over to a PC.

“I do have his password,” he said. “But under normal circumstances, I would never dream of opening up a coworker’s computer without their permission.”

“You have the police’s permission. That should cover it.” Jeppe wheeled his chair over next to Jim. “Please open up his email. He may have bought a plane ticket.”

Jim found the email program. Jeppe leaned closer to the screen.

“Just go through them slowly,” Jeppe instructed. “Thanks.”

Jim scrolled through the emails, moving back in time from the present. Meeting notifications and reports slid by their eyes in a soup of inconsequential information.

Gitte cleared her throat.

“Do you think this has something to do with the body in the silo?” she asked uncertainly.

Jeppe didn’t respond, his focus entirely on the screen. They had reached Thursday afternoon when a familiar sender’s name appeared on the screen.

Henrik Dreyer-Hoff.

“Open that email.”